Orientating a rigid body without changing its position is required in many technical applications. This manipulation task is accomplished by manipulators (spherical manipulators) that are just able to make the end effector move according to controlled spherical motions. Spherical manipulators can be either serial or parallel. Parallel architectures are usually more stiff and precise than the serial ones, whereas their structures are more complex than the serial ones. This paper presents a new three-equal-legged spherical parallel manipulator, named the 3-RRS wrist. The 3-RRS wrist is not overconstrained and exhibits a simple architecture employing just three passive revolute pairs, three passive spherical pairs and three actuated revolute pairs adjacent to the frame. The kinematic analysis of the 3-RRS wrist is addressed and fully solved. Finally, its singularity conditions are written in explicit form and discussed. The results of this analysis lead to the conclusion that the new manipulator has only two types of singularities both easy to be identified with geometric reasoning.
Skip Nav Destination
e-mail: rdigregorio@ing.unife.it
Article navigation
September 2004
Technical Papers
The 3-RRS Wrist: A New, Simple and Non-Overconstrained Spherical Parallel Manipulator
Raffaele Di Gregorio
e-mail: rdigregorio@ing.unife.it
Raffaele Di Gregorio
Department of Engineering, University of Ferrara, Via Saragat, 1, 44100 Ferrara, Italy
Search for other works by this author on:
Raffaele Di Gregorio
Department of Engineering, University of Ferrara, Via Saragat, 1, 44100 Ferrara, Italy
e-mail: rdigregorio@ing.unife.it
Contributed by the Mechanisms and Robotics Committee for publication in the JOURNAL OF MECHANICAL DESIGN. Manuscript received Oct. 2000; rev. Feb. 2004. Associate Editor: Q. Jeffrey Ge.
J. Mech. Des. Sep 2004, 126(5): 850-855 (6 pages)
Published Online: October 28, 2004
Article history
Received:
October 1, 2000
Revised:
February 1, 2004
Online:
October 28, 2004
Citation
Di Gregorio, R. (October 28, 2004). "The 3-RRS Wrist: A New, Simple and Non-Overconstrained Spherical Parallel Manipulator ." ASME. J. Mech. Des. September 2004; 126(5): 850–855. https://doi.org/10.1115/1.1767819
Download citation file:
Get Email Alerts
DeepJEB: 3D Deep Learning-Based Synthetic Jet Engine Bracket Dataset
J. Mech. Des (April 2025)
Design and Justice: A Scoping Review in Engineering Design
J. Mech. Des (May 2025)
Related Articles
Discussion: “Kinematics of a New High-Precision Three-Degree-of-Freedom Parallel Manipulator” ( Tahmasebi, F., 2007, ASME J. Mech. Des., 129, pp. 320–325 )
J. Mech. Des (March,2008)
Application of Workspace Generation Techniques to Determine the Unconstrained Motion of Parallel Manipulators
J. Mech. Des (March,2004)
Related Proceedings Papers
Related Chapters
Time-Varying Coefficient Aided MM Scheme
Robot Manipulator Redundancy Resolution
Feedback-Aided Minimum Joint Motion
Robot Manipulator Redundancy Resolution
QP-Based Self-Motion Planning
Robot Manipulator Redundancy Resolution